Chromium
- Formula: Cr
- Molecular weight: 51.9961
- IUPAC Standard InChI: InChI=1S/Cr
- IUPAC Standard InChIKey: VYZAMTAEIAYCRO-UHFFFAOYSA-N
- CAS Registry Number: 7440-47-3
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: Chromium atom
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- Information on this page:
- Other data available:
- Data at other public NIST sites:
- NIST Atomic Spectra Database - Lines Holdings (on physics web site)
- NIST Atomic Spectra Database - Levels Holdings (on physics web site)
- NIST Atomic Spectra Database - Ground states and ionization energies (on physics web site)
- Gas Phase Kinetics Database
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Ion clustering data
Go To: Top, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Michael M. Meot-Ner (Mautner) and Sharon G. Lias
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
+
= (
•
)
By formula: Cr+ + Cr = (Cr+ • Cr)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 150. ± 20. | kJ/mol | ICRCD | Houriet and Vulpius, 1989 | gas phase |
| ΔrH° | 180. | kJ/mol | EI | Hilpert and Ruthardt, 1987 | gas phase; from IP(Cr2) by EI and D(Cr2) by Knudsen cell, and IP(Cr) |
| ΔrH° | 180. ± 20. | kJ/mol | KC-MS | Hilpert and Ruthardt, 1987 | gas phase; data as evaluated by Houriet and Vulpius, 1989 |
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 125. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( •
) +
= (
• 2
)
By formula: (Cr+ • Cr) + Cr = (Cr+ • 2Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 194. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 2
) +
= (
• 3
)
By formula: (Cr+ • 2Cr) + Cr = (Cr+ • 3Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 100. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 3
) +
= (
• 4
)
By formula: (Cr+ • 3Cr) + Cr = (Cr+ • 4Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 215. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 4
) +
= (
• 5
)
By formula: (Cr+ • 4Cr) + Cr = (Cr+ • 5Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 171. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 5
) +
= (
• 6
)
By formula: (Cr+ • 5Cr) + Cr = (Cr+ • 6Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 246. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 6
) +
= (
• 7
)
By formula: (Cr+ • 6Cr) + Cr = (Cr+ • 7Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 217. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 7
) +
= (
• 8
)
By formula: (Cr+ • 7Cr) + Cr = (Cr+ • 8Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 249. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 8
) +
= (
• 9
)
By formula: (Cr+ • 8Cr) + Cr = (Cr+ • 9Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 232. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 9
) +
= (
• 10
)
By formula: (Cr+ • 9Cr) + Cr = (Cr+ • 10Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 248. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 10
) +
= (
• 11
)
By formula: (Cr+ • 10Cr) + Cr = (Cr+ • 11Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 258. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 11
) +
= (
• 12
)
By formula: (Cr+ • 11Cr) + Cr = (Cr+ • 12Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 289. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 12
) +
= (
• 13
)
By formula: (Cr+ • 12Cr) + Cr = (Cr+ • 13Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 294. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 13
) +
= (
• 14
)
By formula: (Cr+ • 13Cr) + Cr = (Cr+ • 14Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 267. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 14
) +
= (
• 15
)
By formula: (Cr+ • 14Cr) + Cr = (Cr+ • 15Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 282. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 15
) +
= (
• 16
)
By formula: (Cr+ • 15Cr) + Cr = (Cr+ • 16Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 273. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 16
) +
= (
• 17
)
By formula: (Cr+ • 16Cr) + Cr = (Cr+ • 17Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 208. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 17
) +
= (
• 18
)
By formula: (Cr+ • 17Cr) + Cr = (Cr+ • 18Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 233. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 18
) +
= (
• 19
)
By formula: (Cr+ • 18Cr) + Cr = (Cr+ • 19Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 289. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
( • 19
) +
= (
• 20
)
By formula: (Cr+ • 19Cr) + Cr = (Cr+ • 20Cr)
Enthalpy of reaction
| ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 253. | CID | Armentrout and Kickel, 1994 | gas phase; guided ion beam CID |
References
Go To: Top, Ion clustering data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Houriet and Vulpius, 1989
Houriet, R.; Vulpius, T.,
Formation of Metal Cluster Ions by Gas - Phase Ion - Molecule Reactions: the Bond Energies of Cr2+ and Mn2+,
Chem. Phys. Lett., 1989, 154, 5, 454, https://doi.org/10.1016/0009-2614(89)87130-1
. [all data]
Hilpert and Ruthardt, 1987
Hilpert, K.; Ruthardt, K.,
Determination of the dissociation energy of the Cr2 molecule,
Ber. Bunsen-Ges. Phys. Chem., 1987, 91, 724. [all data]
Armentrout and Kickel, 1994
Armentrout, P.B.; Kickel, B.L.,
Gas Phase Thermochemistry of Transition Metal Ligand Systems: Reassessment of Values and Periodic Trends, in Organometallic Ion Chemistry, B. S. Freiser, ed, 1994. [all data]
Notes
Go To: Top, Ion clustering data, References
- Symbols used in this document:
T Temperature ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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